Letzkau was founded by the Teutonic Knights under the Chełmno law (Kulm Law, a legal constitution for a municipal form of government) in 1384. In 1552, the charter was confirmed by King Sigismund II Augustus (Zygmunt II August) of Poland. The village was completely destroyed multiple times -- in 1458 by the Teutonic Knights and then in 1626 by the Swedes.

Until 1793 Letzkau was part of Danzig in Royal Prussia (also known as Polish Prussia) in the Kingdom of Poland. The Second Partition of Poland in 1793 added Danzig and its surrounding territory to the province of West Prussia. Letzkau was situated in the district (Kreis) of Danzig from 1818 until 1887, when it became part of the district of Danziger Niederung. Letzkau became part of the Free City of Danzig from 1920 until the outbreak of World War II in 1939, when it came under the control of Nazi Germany. In February 1945 it was occupied by Soviet forces and eventually returned to Poland. In 2012 Letzkau (now Leszkowy) was a village in the administrative district of Gmina Cedry Wielkie, within Gdańsk County, Pomeranian Voivodeship.

In 1820, Letzkau had 350 residents, including nine Mennonites. In the 2nd half of the 19th century, the village had 4,403 morgas (2,635 hectares) of land, 197 Catholics, 339 Lutherans, two Mennonites, and 37 houses.

Mennonites who were residents of Letzkau were members of the Bärwalde Mennonite Church.